/*
 * Copyright 2018- The Pixie Authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * SPDX-License-Identifier: Apache-2.0
 */

#pragma once

#include <chrono>
#include <functional>
#include <memory>

namespace px {
namespace event {
/**
 * Callback for timer after expiration.
 */
using TimerCB = std::function<void()>;

/**
 * Timer is an abstract timer event.
 */
class Timer {
 public:
  virtual ~Timer() = default;

  /**
   * Disable pending timeout without destroying the timer.
   */
  virtual void DisableTimer() = 0;

  /**
   * Enable a pending timeout. If a timeout is already pending, it will be reset to the new timeout.
   * @param ms supplies the duration of the alarm in milliseconds.
   */
  virtual void EnableTimer(const std::chrono::milliseconds& ms) = 0;

  /**
   * Return whether the timer is currently armed.
   */
  virtual bool Enabled() = 0;
};

using TimerUPtr = std::unique_ptr<Timer>;

}  // namespace event
}  // namespace px
